The "technology" forum has discussions comparing BOSE with Etymotics, run a search.

I don't like th etymotics, I constantly feel them poking in my ears though the sound is great, but perhaps if I had them custom made to fit my weird ears maybe I'd like them better. You can also rest your head on its side with them in to sleep, which you can't easily do with the BOSE.

Over time, the BOSE make my earlobes hurt from all the compression and I need to give the lobes a break periodically, but I still love them and hate it when I can't wear them at take-off landing (most FAs on NW or CO have not enforced this but on AS they are headphone Nazis)